The specific aims of this project are to: a) develop written protocols for utilizing a diagnostic rapid testing algorithm, b) identify best practices for implementation, c) evaluate the advantages and disadvantages of such an algorithm, d) to validate the use of a diagnostic rapid HIV testing algorithm, e) assess the proportion of non-HIV-infected clients who receive a preliminary positive result according to the algorithm as opposed to current practice, f) assess the proportion of HIV-infected clients who receive disclosure of a confirmed HIV positive test result according to the algorithm as opposed to current practice, g) assess the proportion of HIV-infected clients who are referred to and receive primary medical care as a result of diagnosis through the algorithm as opposed to current practice, h) assess the cost of HIV testing with a diagnostic algorithm. The broad, long-term objectives of this project are in line with the agencies' missions to: a) increase the number of HIV-infected individuals who learn their status and enter into early medical care and prevention services to prevent transmission to others, b) reduce the burden of rapid HIV testing program implementation and maintenance on the staff of performance sites, and c) improve the efficiency and quality of HIV testing services available for high-risk and hard to reach clientele. Seven intervention sites will be providing rapid HIV testing according to the following algorithm: an FDA approved CLIA-waived rapid test will be run. If the test is reactive, a second CLIA-waived rapid test will be run. If that test is also reactive, the client will be diagnosed as HIV-positive and linked to medical care. Blood will be drawn and an appointment will be scheduled for one week later to disclose the results of confirmatory testing. If the second rapid test is non-reactive, then a third rapid test will be run to determine diagnosis and blood will be drawn for confirmation. Thirteen comparison sites will be providing rapid HIV testing according to the current standard of practice: a CLIA-waived rapid HIV test is run, and if preliminary positive, blood is drawn for confirmation. At the confirmatory disclosure appointment one week later, the client is diagnosed with HIV and linked to medical care. Assistance will be provided to both intervention and comparison sites to enhance the tracking of linkages to medical care and other necessary support services for all individuals testing HIV-positive. This research is relevant to public health because early identification of HIV-positive people and linkage to medical care reduces the rate of transmission and the burden of providing late-diagnosis medical care.